Vertical Deformation Monitoring of the Suspension Bridge Tower Using GNSS: A Case Study of the Forth Road Bridge in the UK

A study monitoring the vertical deformation of the Forth Road Bridge's southern tower reveals a subsidence rate of approximately 4.7 mm per year, with high precision and minimal uncertainty. The research employed advanced GNSS data processing techniques to analyze 33 months of deformation data, identifying significant seasonal signals linked to thermal effects. A thermal expansion model demonstrated a 98.9% consistency with observed annual signal amplitudes, underscoring the substantial impact of temperature variations on bridge tower deformation. While daily signal amplitudes showed poor correlation with ambient temperature, their phase variations aligned closely post-February 2016. The study also explores the potential influence of the North Atlantic Drift on these signals due to the bridge's unique geographical location. It emphasizes the need for more detailed meteorological and loading data to further investigate deformation mechanisms over time.

Chen, Q., Jiang, W., Meng, X., Jiang, P., Wang, K., Xie, Y., & Ye, J. (2018). Vertical Deformation Monitoring of the Suspension Bridge Tower Using GNSS: A Case Study of the Forth Road Bridge in the UK. Remote Sensing, 10(3), 364. https://doi.org/10.3390/rs10030364